Problem $1.(10$ points$)$

A manager recorded the number of gallons of ice cream sold for the past eight petiods. He asked you to

choose a forecasting model to predict the demand for gallons of ice cream in Period $9.$ You consider

applying a three$-$period moving average model and a three$-$period weighted moving average model with

weights of $0\mathrm{.}45,0\mathrm{.}35$ and $0\mathrm{.}2.$

a$)$ Which model is better for this data set $($hint: show all your work including forecasts for each period and

calculations using measures of forecast accuracy$)?(9$ points$)$

b$)$ What is the forecast of demand for period $9$ when you use the best model for the data? $(1$ point$)$